JP2003505252A - Method and apparatus for forming opposing holes in sidewalls of a tubular workpiece - Google Patents

Abstract

A method of cutting opposing holes in a side wall of a tubular workpiece and removing the cut out slugs, in which first and second axially aligned punches are applied to opposite side walls of a pressurized workpiece. The second punch has a larger width than the first punch, and reciprocates in a passageway extending laterally from the workpiece. The punches are reciprocated so that the first punch passes through both side walls, and first and second slugs are cut out. The end of the first punch is advanced toward the end of the second punch to capture the cut out slugs between the ends of the first and second punches, and the punches are moved so that the ends of the punches and the slugs captured between them progress along the passageway away from the workpiece. The ends of the punches are separated at a region of the passageway spaced from the workpiece, and the released slugs are removed from the ends of the punches.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a method and apparatus for forming two opposing holes in a sidewall of a tubular workpiece and for removing slugs cut from it. This method is usually
The inside of the tubular work piece is applied, for example under pressure by means of pressurized water, and hydroforming is carried out in the cavity of the mold. Nowadays, this hydroforming method is used for large scale manufacturing such as manufacturing frame constituent members in road vehicles. Opposed or linear holes are often required for tubular frame members or the like, such as those for mechanically connecting fasteners therethrough.

[0002]

[Prior art]

A conventionally known method for forming holes is described in US Pat. No. 4,989,482 (Mason).
), There is disclosed a reciprocating member or punch having a pointed working end for piercing the sidewall of a pressurized workpiece and for cutting off the slug. According to it, the punch is provided with a hole, for example with a bore connecting between the working end and the low-pressure zone in order to promote the attachment of slag to the working end of the punch. This avoids the problem of the cutting slag peeling off the punch, falling into the workpiece, and remaining at an unknown location within the workpiece after the hole forming operation is complete. However, while the above patent discloses a procedure for forming one hole, it does not disclose a procedure for forming two aligned holes.

In other known methods, for example, US Pat. No. 3,495,486 (Fuchs)
Discloses a member that reciprocates in a passage adjacent to a pressurized workpiece. Initially, the working end of the member is supported adjacent to the sidewall of the workpiece.
The working end is pulled down from the workpiece and internal pressure acts in liquid form on the punch, cutting off the slug from the sidewall in the unsupported area along the line corresponding to the perimeter of the passage.
The above patent does not disclose the excision of holes aligned against each other, nor does it mention the disposal of slag after hole formation.

US Pat. No. 5,666,840 (Shah et al.) Discloses a method of piercing a hydroformed tube with two aligned holes. The punch is perforated and it is recommended that the slag adhere to the cutting end of the punch. This method relies on liquid pressurization to provide slag removal pressure from the end of the punch into the tube. As a result, pressure is required to be maintained during and after the formation of the second hole, and the second hole must be the same size as the punch, which is a design constraint, which The punch is sealed as it passes. In addition, the passage in the die or die button adjacent to the second hole is the same size as the punch, thus introducing the risk of rapid fatigue or breakage of the punch. Also, a slight misalignment causes the punch to hit the side of the die button. A further disadvantage of the above device is that if for some reason the pressure in the tube is compromised, the slug will be pulled back in the tube and will deposit in the tube when the punch retracts. The presence of slag does not appear until after the water film has dried up, as the slag adheres to the water film inside the sidewalls of the tube, and it is a nuisance after the tube product is shipped or incorporated into a vehicle frame or other product. It is difficult and impossible to bail out the buyer.

[0005]

[Problems to be Solved by the Invention]

The present invention provides a method and apparatus for overcoming the disadvantages of the above conventional methods.

[0006]

[Means for Solving the Problems]

According to the present invention, a hole facing a side wall of a tubular work piece is excised, and a slag is removed from the hole, which comprises the following steps.

(A) Applying pressure to the workpiece (b) Providing first and second reciprocating members, each having a working end and aligned in the axial direction, said working end facing the workpiece A second member, which is applied to the first and second walls and has a larger cross section than the first member, reciprocates in a passage extending in a direction crossing the workpiece. (C) First and second The first member penetrates the two-wall portion. (D) The first and second slugs are cut from the first and second wall portions of the workpiece. (E) The working end of the first member is the working end of the second member. In a direction to capture the cutting slug between the working ends of the first and second members (f) move the upper member, thereby moving the working ends of the members and the slugs captured therebetween. Propagate along the path away from the workpiece (g) the member The working end, in the region of the passageway spaced from the workpiece, the method of the separation to (h) above the working end removing the slag.

By the method according to the invention, the passage through which the second member reciprocates has a larger cross-section than the first member, so that the hole formed in the side wall of the tubular workpiece adjacent to the second member is Wider than the hole formed in the side wall of the workpiece adjacent to one member, and there is a clearance between the first member and the side of the passage, thus significantly reducing the risk of the first member colliding with the side of the passage. Or it is avoided. Opposing first and second
The slugs trapped between the members are moved together as a unit outside the tube, where they are reliably released by the separation of the working ends of each member, at which point the slag removal technique, namely the first and second members A jet of compressed air and pressurized water to separate the slag is applied. It also ensures that the slag is not pulled back inside the tubular workpiece. The above-mentioned method can supply pressure from a pressure source other than the liquid used for pressurizing the tube to remove the slag from the ends of the first and second members.

The present invention also provides an apparatus for cutting opposing holes in a sidewall of a pressurized tubular workpiece and removing slag therefrom.

(A) first and second opposing dies for limiting the pressurized work piece; and (b) reciprocating in a first passage of the first die to create a first work piece of the work piece. A first member having a working end applied to the wall portion; and (c) reciprocating in a second passage of the second die and applied to the second wall portion of the workpiece facing the first wall portion. And a second member having a larger cross section than the first member and (d) a region separated from the workpiece, the cloth for slag treatment in the second die communicating with one side of the second passage. And (e) reciprocating the first and second members so that the first member is provided between the portion having the working end portion adjacent to the first wall portion and the portion adjacent to the cross passage. Reciprocally operable and having a working end adjacent to the second wall portion Is operable to reciprocate between the second portion and a portion adjacent to the cross passage, and (f) a first portion connectable to the cross passage for moving the slag along the cross passage. A device comprising a pressure source of 1.

[0011]

DETAILED DESCRIPTION OF THE INVENTION

  An embodiment of the present invention will be described below with reference to the drawings.

In the accompanying drawings, the same reference numerals indicate the same parts, and
4 shows the method, FIG. 1 is a pressing device with upper and lower dies 11 and 12 applied in a hydroforming operation, a workpiece in the form of a tube 13 between the dies 11 and 12 in the closed position. Confined within the cavity 14 formed.

In the preferred form, the ends of the tube 13 are sealed by a fluid 16 such as water, which fills the tube 13. The liquid is preferably die 11
, 12 is pre-pressurized before closing. After the die is closed, the "fluid 16" is further pressurized, so that the tube wall 17 conforms to the contour of the cavity 14. Hydroformed tube products often have a rectangular cross-section rather than a circle. The pre-pressurizing, hydroforming, filling and sealing steps are described in commonly owned U.S. Pat. No. 33,990 (Reissue) (Cudini), 5,235,836, the entire disclosure of which is incorporated herein by reference. No. (Klages et al.), No. 5,445,0
02 (Cudini et al.) And 5,644,829 (Mason et al.).

The first member or punch 18 reciprocates within a laterally extending passageway or bore 19 defined by the upper die 11 in the die cavity. The structure and function of punch 18 is described in US Pat. No. 4,989,482 (Mason).

The punch 18 has a working end or tip 20 and is carved to form a cutting edge, the preferred form of which is an axial bore extending inwardly from the working end 20. 21 having a cross bore 22 which bends outwardly of the punch 18.
Communicate with. The punch 18 also holds a holder 23 connected to a device 24 for reciprocating the punch, for example the holder 23 of the punch is connected to the piston of a hydraulic piston and the cylinder (not shown) of the cylinder device is It is connected to the die 11.

A supply cross bore 26 extends through the die 11 and has one end connected to the lateral bore 19, which further comprises a valve 27 to a pressurized fluid source S ₁ such as compressed air.
Connected through.

The die 12 has passages or bores 28 aligned with the rows of passages 19 that extend laterally to the cavity 14 formed by the die 12. Second member 29
Reciprocate in the passage 28. The second member 29 and the passage 28 are slightly wider than the first member 18 and the passage 19, and in a preferred form, as shown in FIG. In position, punch 18
Is inserted into the passage 28 with a clearance all around. For example, the punch 29 and the passage 28 are about 0.5 to 30 more than the punch 18 with respect to the width of the punch 18.
It can be 0% wider, more preferably about 5 to 100%, and even more preferably 10 to 20% wider than the punch 18. The member 29 preferably has a working end or tip 20 and may be skived to form a cutting edge.

Member 29 also has an axial bore 32 extending from its working end 20 to a cross bore 33 extending outwardly of member 29. Said member 29 carries a holder 34 which is connected to a device 36 for reciprocating said member, for example said holder 34 is connected to the piston of a hydraulic piston and the cylinder (not shown) of the cylinder device is a die. It is connected to 12.

A chute or cross passage 37 for disposing of slag traverses the passage 28, one side of which slopes downward toward an exit end (not shown) on one side of the die 12. The inner end of the chute 37 on the opposite side of the passage 28 penetrates the die 12 and connects via a valve 41 to a source S _{2 of} pressurized fluid, for example pressurized water, which feed bore 39.
It is connected to the. The bore 39 can be connected to the passage 38 through a portion limited by a constriction 42 such as a jet.

The other supply bore 43 is connected at its one end to the outside of the passage 28 in a crossed manner and at the other end to a pressurized fluid source S ₃ such as compressed air via a valve 44.

In operation, the first and second members 18 and 29 initially have their working ends 20 and 31 flush with the adjacent surfaces of the cavities 14 in the dies 11 and 12, as shown in FIG. First and second tubes 13 located and pressurized by the fluid
Touch the outside of the wall.

In one form of the method of the present invention, as shown in FIGS.
Urges the working end 20 of the punch 18 to advance through the contact of the tube wall 17 and cuts the slug 46. As shown in FIG. 2, the working end 20 of the punch 18 carries the slug 46 forward. Therefore, as a preferred form, the punch 18 has a ventilation bore 21, and the attachment of the lug 46 to the working end 20 and the clean cutting and removal of the slug 46 from the tube wall 17 are performed inside the tube 13 and inside the bore 21. Prompted by the pressure difference existing between and. That is, the pressure in the bore 21 is equal to that of the fluid 1.
Compared to 6, the pressure is preferably reduced to substantially atmospheric pressure.

At the point in time when the slug 46 contacts the surface of the second side wall portion of the side wall 17 in the area facing the passage 29, the device 36 operates to retract the member 29, as shown in FIG. . For example, if the device 36 is connected to the piston and cylinder of a hydraulic piston, the valve connected to the cylinder operates to release pressure from the cylinder at the extension of the piston. The device 36 can optionally be actuated such that the member 29 is positively retracted away from the tubular work piece 13, with the slug 46 contacting the second side wall portion and, after a short time, the piston. The pressure is released from the extension side as described above. Due to the combination of the impact of the slug 46 inside the side wall portion 17, the pressure by the pressure fluid 16 in the tube 13 and the lowering of the member 29, the second slug 47 is punched out of the side wall 17 in the area adjacent to the passage 28. . The device 24 and the punch 18 are advanced towards the extended position shown in FIG. 3, the member 29 is pushed backwards together with the holder 34 and the device 36, so that the slur 46 and 47 cause the working ends of the punch 18 and the member 29 to move. Part 2
It is compressed and captured between 0 and 30 and is reliably transported in the captured position to the lateral position shown in FIG. Up to this point, the working ends 20 and 31 oppose each other so that the slugs 46, 47 are compressed and trapped between them, which slugs 46, 47 engage the fluid in the tube 13 and the axial vent bore 21. The pressure difference between the inner side of the inner part and the inner part of the inner part 32 and 32 ensures that the working ends 20 and 31 are positioned and held. As a result, slag 4
7, for example, is cut off cleanly from the side wall of the tube 13 and does not remain attached to the wall.

Since the passage 29 has a larger area than the punch 18, the second slug 47 has a larger area than the slug 46. Further, as is apparent from FIG. 3, a clearance is provided on the sides of the punch 18 and the passage 28 over the entire length thereof so that the punch 18 can move forward.

In order to avoid excessive fatigue of the members of the lower die 12 due to the stress generated by cutting off the second slug 47, the lower die 12 is provided with an opening 28 A for forming the mouth of the passage 28. An insert or die button 48 may be provided in the opening area of the passageway 28. The insert 48 or die button is formed of hard steel, for example.

The punch 18 is advanced until the device 24 is in a position to reach the limit of movement in its extension direction, as shown in FIG. This limit is set, for example, by a piston connected to the cylinder 24 which reaches a limit of movement which is defined by the wall of the cylinder (not shown) in which the piston operates.

In this extended or advanced limit position, the cross bore 22 of the punch 18 is aligned with the feed bore 26 of the die 11, as shown in FIG.

While the punch 18 is stopped, the member 29 is actuated by the device 36 to continue retracting away from the tube 13 up to the limit of retraction shown in FIG.
To do. This is done, for example, by supplying pressure to the piston retract side of the piston and the cylinder mechanism connecting to the device 36. Again, the limit of retraction is determined by the piston connected to the device 36 where the limit of movement within the cylinder in which the piston works is reached.

In the position shown in FIG. 4, the cross bore 33 in member 29 is aligned with the feed 43 bore of die 12.

In the position shown in FIG. 4, the working ends 20 and 31 of the members 18 and 29 are
They are spaced apart from each other, so that the slugs 46 and 47 are released and are no longer trapped in the compressed state between the working ends 20 and 32.

The valves 27, 41 and 44 are opened and compressed air is supplied from the sources S _I and S ₃ to the supply bore 2.
6 and 43, compressed gas is supplied to the axial bores 21 and 32,
Slugs 46 and 47 are propelled axially away from working ends 20 and 31 of members 18 and 29. At the same time, pressurized water, for example under hydraulic or gas pressure, is forced along the feed bore 39, the pressurized water being in the forced spray state shown in broken lines in FIG.
Then, it is discharged into the chute 37, and the slags 46 and 47 are washed down along the slag treatment chute 37 as shown by the arrow in FIG. Water escaping from tube 13 along the annular passage between punch 18 and passage 28 flows to chute 37 and slug 46.
, 47 to help wash out to the exit. The removed slag can be collected in a bin or the like located adjacent the exit end of the chute 37 adjacent the lower die 12 side.

The devices 24 and 36 operate to return the punch 18 and the member 29 to the position shown in FIG. 1, in which the working end of said member is flush with the abutment surface of the cavity 14 of the dies 11 and 12. Placed at height.

The ends of the tube 13 are not sealed so that the remaining liquid is drained from the tube 13 and the dies 11 and 12 are opened to remove the hydroformed and perforated work piece. .

The resulting tubular workpiece is then placed between open dies 11,12, said workpiece being sealed, filled, and preferably prepressed, and the dies 11,1
2 is moved to the closed position, the workpiece is hydroformed and the cycle of operations described with reference to Figures 1 to 4 is repeated.

In a preferred form, the operation of actuating devices 24 and 36 and valve devices 27, 41 and 44 are automatically controlled. This passive control is well known in the art and well known in the art and need not be described at length here. For example, the automatic control may be achieved by a timer or a proximity activated by the device 24,36.
This is accomplished by a logic circuit operated by the proximity switch.

In the second embodiment of the present invention described below with reference to FIGS. 5 and 6, the member 29
Acts as a punch and preferably has a pointed working end or tip 31.

Initially, members 18 and 29 are in the position shown in FIG. The device 36 operates to drive the punch 29 through the side wall 17 of the pressurized tube 13,
7 is cut off and an opening corresponding to the side wall 17 is formed. As shown in FIG. 5, the slug 47 is carried to the tip portion 31 of the punch 29 so as to move to a substantially central position in the tube 13. The adhesion of the slug 47 to the tip portion 31 causes the fluid 16 in the tube 13 to adhere.
Is favored in a favorable manner by the pressure difference existing between and inside bore 32 in passageway 29.

The punch 29 is tightly fitted within the passage 28, but normally the punch 29 and the passage 2 are
The fit between the eight is not gas honey and therefore the inside of the passage 32 has at least some space to communicate with the outside air.

Desirably, the leakage of pressure water from the tube 13 is reduced, and the slugs 46, 4
Passages 19 and 28 may be equipped with O-rings to maintain the desired degree of pressurization within tube 13 after 7 has been cut from the side wall of the tube. The ring is retained in an annular groove in the sidewall of the passageway 19 or 28, and the punches 18 and 29 are
The sides and also seals between the sidewalls of passages 19 and 28 and conventional punches 18 and 29.

The device 24 then operates to drive the punch 18 through the adjacent side wall 17 to ablate a slug 46 having a smaller area than the slug 47. The punch 18 continues to advance to the position shown in FIG. 6 where it is captured in compression between the tips of the 46 and 47 members 18 and 29. The punch 18 advances, while the punch 29
For example, as shown in FIG. 3, it is retracted by releasing the pressure on the extension side of the piston connected to the device 36. The punch 18 has its captured slugs 46 and 4
Pushing the punch 29 together with 7, the slugs 46 and 47 remain trapped between the working ends of the punches 18 and 29. Slugs 46 and 47 captured as described above
Move integrally to the position shown in FIG. 3 where the punch 18 reaches the extension limit. The rest of the operating cycle is then as described with reference to FIGS. 3 and 4, in which position the member 29 is retracted further and the slug 46 is removed.
And 47 are moved by the compressed air supplied along the supply bores 26 and 43, and the slugs 46 and 47 which have been freed by the water jet supplied from the bore 39 are flown out below the slag chute.

After that, the punches 18 and 29 are returned to the positions shown in FIG. 1, the opened workpiece and the seal are removed, and the drainage treatment is performed. After the dies 11 and 12 are opened, they are taken out from the pressing device. The new workpiece is then cycled through the operations described with reference to FIGS.

A third form of the method of the present invention is shown in FIG. 7 with the punches 18 and 29 initially in the position shown in FIG. 1 and the punch 18 retracted as shown in FIG. Then, 46 attached to the working end 20 of the punch 18 is pushed out by the pressure in the tube 13.

The punch 18 carrying the slug 46 is advanced to the position shown in FIG. 2 and follows the operation described with reference to FIGS. 2, 3 and 4.

In a fourth form of the above method, initially following the procedure described above with reference to FIG. 7, the punch 29 then carries the slug 47 to an inward position within the tube 13, as shown in FIG. . The punch 18 is advanced to the position shown in FIG. 6 and follows the procedure described above with reference to FIGS.

In the fifth form of the method, as shown in FIG. 9, initially, the punch 18 is advanced to cut the slug 46 and the punch 29 is retracted. The fluid pressure in the tube 13 thereby cuts off the slug 47. Then the punch 18 moves forward, while
The punch 29 is retracted and follows the procedure described above with reference to FIGS.

In the sixth form of the above method, initially the punches 18 and 29 are both retracted, as shown in FIG. 10, to excise the slugs 46 and 47 with the pressure in the tube 13. The punch 18 advances, while the punch 29 retracts, after which the procedure described above with reference to FIGS. 3 and 4 is followed.

The cross-sectional shape of the members 18 and 29, and thus the desired contours of the slug cut portion by their working ends and the opening formed in the side wall 17, may be, for example, circular, elliptical, triangular, rectangular, multi-shaped. It has a prismatic or simple or complex curved shape. On the other hand, the passage 28, including the passage 28A through which the member 29 and die button 48 pass, has a greater width and cross-sectional area than members 18 and 19, but the total cross-sectional area of member 29
It does not need to be greater than 8. It is desired that the member 18 pass through the passageway 28 with a rear lance along its entire length.

For example, when the cross section of the punch 18 is projected onto the cross section of the member 29, it is sufficient that all outer edges thereof have a margin or clearance inside the cross section of the member 29. The risk of the punch 18 colliding with the side of the passage 28 or die button 48 can be avoided.

The method described above provides yet another advantage, in which the slugs 46, 47 are sharply cut from the wide wall of the tube 13 and securely captured and inside the chute 37 away from the workpiece. It moves, is released there, and is processed along the chute 37. This eliminates the risk of the slugs 46, 47 being reversed or left behind in the tubular workpiece 13.

The sidewall 17 of the tube 13 adjacent to the hole formed by cutting the slug 46 tends to be indented in the center of the tube 13 due to the inward movement of the slug 46 made by the punch 18. On the other hand, on the other hand, the outward movement of the larger slug 47 tends to be pushed outwards against the face of the cavity 14, so that the periphery of the hole formed by the removal of the slug 47 is tubular. It tends to be formed at the same height as the side wall 17. This shape around the holes is particularly convenient and practical for mounting mechanical stops through the aligned holes.

[Brief description of drawings]

FIG. 1 is a schematic view showing a part of a hydroforming die cut out before starting a punching operation according to an embodiment of the present invention.

[Fig. 2]     Explanatory drawing which shows the process of punching and the removal operation of slag.

[Figure 3]     Explanatory drawing which shows the process of punching and the removal operation of slag.

[Figure 4]     Explanatory drawing which shows the process of punching and the removal operation of slag.

[Figure 5]     The figure which shows the modification of the punching method which is another Example of this invention.

[Figure 6]     Explanatory drawing which shows the process in the punching method shown in FIG.

[Figure 7]     The figure which shows the modification of the punching method which is another Example of this invention.

[Figure 8]     The figure which shows the modification of the punching method which is another Example of this invention.

[Figure 9]     The figure which shows the modification of the punching method which is another Example of this invention.

[Figure 10]     The figure which shows the modification of the punching method which is another Example of this invention.

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Claims (22)

[Claims] 1. A method for cutting a hole facing a side wall of a tubular workpiece and removing slag from the hole, which comprises the following steps. (A) Pressurize the workpiece. (B) Provide first and second axially aligned reciprocating members, each having a working end, said working end comprising a first and a second opposing work piece. A second member having a cross section larger than that of the first member and arranged to be applied to the second wall, and reciprocates in a passage extending in a direction crossing the workpiece. (C) First and second wall portions The first member penetrates (d) the first and second slugs are cut from the first and second wall portions of the workpiece (e) the working end of the first member is advanced toward the working end of the second member Capturing the cutting slug between the working ends of the first and second members (f) moving the upper member, thereby moving the working ends of said member and the slag caught between them from the workpiece. Advancing along the passage in a direction away from (g) the working end of the member, Separation in the area of the passage away from the workpiece (h) A method of removing the slag from the working end. 2. The first member has a cutting end and the steps (c) and (d) advance the first member through the first wall portion toward the second wall portion. The method of claim 1, wherein the second member is retracted away from the workpiece after the first member is proximate the second wall portion. 3. The first and second members each have a cutting action end, and the steps (c) and (d) pass through the first and second wall portions to obtain the first and second members. 2. A method according to claim 1 including the steps of advancing each of them toward the interior of the workpiece and causing the first to advance through the second wall portion while retracting the second member outwardly from the workpiece. 4. The method of claim 1, wherein the steps include retracting the first member laterally away from the workpiece and advancing the first member laterally through the second wall portion. 5. The steps (c) and (d) include retracting the first member laterally away from the workpiece, advancing the first member laterally through the second wall portion, and removing the second member. 2. A step of retracting laterally away from the workpiece.
The method described in. 6. The method of claim 5, wherein the second member is retracted before the first member is proximate the second wall portion. 7. The method of claim 5, wherein the first member is retracted after the first member is in proximity to the second wall portion. 8. The steps (c) and (d) advance the first member through the first and second wall portions, prior to the first seat right approaching the second wall portion. Two
The method of claim 1 including retracting the member away from the workpiece. 9. Steps (c) and (d) include retracting the first and second members away from the workpiece and forcing the first member through the first and second wall portions. The method of claim 1. 10. The first and second members have axial bores respectively communicating between the working end and a rear portion of the member, the step (h) comprising: A method as claimed in any one of the preceding claims including the step of applying pressure along each axial bore. 11. The method of claim 10, wherein the first and second members have a cross bore communicating with the axial bore and are aligned with a pressure conduit connecting to a pressure source. 12. The first and second members reciprocate in first and second dies, each pressure conduit having a bore extending into the first and second dies, respectively. Method. 13. The passage communicates with a cross passage in a region away from the workpiece, wherein the step (h) applies pressure from a part of the cross passage to one side of the passage, The method according to claim 1, wherein the slag is moved in the direction of the cross passage on the side of the passage opposite to the passage. 14. A device for cutting opposing holes in a sidewall of a tubular workpiece and removing slag therefrom, comprising: (a) opposing first and second limiting means for limiting the pressurized workpiece. A second die; (b) a first member having a working end reciprocating in a first passage of the first die and applied to a first wall portion of a workpiece; and (c) the second die. A second member reciprocating in a second passage of the die and having a working end applied to the second wall portion of the workpiece opposite the first wall portion and having a larger cross section than the first member. And (d) a cross passage for slag treatment in the second die that communicates with one side of the second passage in a region separated from the workpiece, and (e) reciprocates the first and second members, A portion having a working end adjacent to the first wall portion and the cross passage A second member operable to reciprocate the first member between adjacent portions and between a portion having a working end adjacent the second wall portion and the portion adjacent the cross passage. And (f) a device having a first pressure source connectable to the cross passage for moving the slag along the cross passage. 15. The first member has a cut working end.
The device according to 4. 16. The second member has a cut working end.
Or the device according to 15. 17. The apparatus according to claim 14, wherein the reciprocating drive mechanism of the first member is operable to retract the first member away from the workpiece. 18. The reciprocating drive mechanism for the second member is operable to extend the second member through the second wall portion toward the interior of the workpiece.
18. The device according to any one of 1 to 17. 19. The other pressures, wherein the first and second members each have an axial bore communicating between the working end and a rear portion of the member, the pressure being connectable along each axial bore. 19. A device according to any of claims 14 to 18 comprising a source. 20. The first and second members each have a cross bore communicating with an axial bore, and when the working end of the member reciprocates to a position in contact with the cross passage,
20. The device of claim 19 aligned with each pressure conduit. 21. The apparatus of claim 20, wherein each pressure conduit has a bore extending into the first and second dies. 22. The apparatus according to claim 14, wherein the first pressure source is connected to a part of the cross passage on one side of the second passage opposite to the one side.